“Old Sol has been meddling with our science. No Fair!”
Not to mention the cosmic ray intensity may be another variable, could get stronger or weaker, sync up with our suns cycles.
“space” weather and how it impacts terrestrial weather is probably far more complicated then they think.
That’s also true, external sources of these rays may wax or wane according to whatever stars recently blew up and other galactic level phenomena.
In fact, trying to stave off ice ages may be the bigger challenge.